Pyrgus cacaliae - Dusky Grizzled Skipper
This large Pyrgus has been around whenever I have looked in the high Alps. I have found it to be more amenable to being photographed compared with the Large Grizzled Skipper most similar in appearance.
The brownish grey ground colour with small forewing spots and hindwing bereft of markings are fairly easily distinguishable in the field, making identification relatively easy, ( for this difficult genus). I have seen it not uncommonly in the Alps and it has behaved for butterfly photos.